Automatic driveshaft coupler for auto header hookup

ABSTRACT

An agricultural harvester ( 100 ) comprises a self-propelled vehicle ( 102 ); a feederhouse ( 104 ); a driveshaft ( 114 ) supported on the feederhouse ( 104 ), the driveshaft ( 114 ) having a first coupler ( 116 ) fixed to one end of the driveshaft ( 114 ), the first coupler ( 116 ) comprising a coupler body ( 420 ), a piston ( 416 ) disposed in the coupler body ( 420 ), and a first key ( 302 ) mechanically coupled to the piston ( 416 ) to be extended or retracted by the piston ( 416 ) to engage a mating coupler on a second driveshaft ( 120 ) of an agricultural harvesting head ( 106 ) that is supported on the feederhouse ( 104 ).

FIELD

The field is agricultural work vehicles. More particularly the field isshaft couplers for coupling agricultural harvesting heads to harvestingvehicles.

BACKGROUND

Agricultural work vehicles such as agricultural harvesters travelthrough agricultural fields harvesting crops. These vehicles aretypically arranged into 2 major subcomponents that are selectivelycoupled together.

The first subcomponent is the harvesting vehicle. The harvesting vehicleis configured to gather the cut crop material, thresh the grain,separate the grain from the material other than grain (MOG), clean thegrain, and store the grain until it can be unloaded from the vehicle.Harvesting vehicles such as this are typically called “combineharvesters” or “combines”.

The second subcomponent is the agricultural harvesting head. Theagricultural harvesting head is configured to engage a particular cropor crops as it travels through the field supported on the front of theharvesting vehicle, to separate the crop from the ground, and to conveythe crop to the harvesting vehicle. Agricultural harvesting heads arespecially configured based upon the crop or crops they are designed toharvest, which typically include such crops as wheat, soybeans, corn,rice, and rapeseed.

Agricultural harvesting heads are typically mounted on a supportstructure called a “feederhouse” that extends forward from the front ofthe harvesting vehicle. They include components such as conveyor belts,augers, and reciprocating knives that are driven by an internalcombustion engine mounted on the harvesting vehicle.

To connect the two together, the vehicle operator maneuvers the vehicleuntil the feederhouse and the agricultural harvesting head are aligned.The operator then climbs down from the harvesting vehicle, approachesthe front of the harvesting vehicle, and manually couples the harvestingvehicle and the agricultural harvesting head together.

Once the two are connected, the operator then returns to the latter,climbs up to the operator station, and starts the vehicle. This is atime-consuming process.

What is needed, therefore, is a more efficient means of coupling theagricultural work vehicle to an agricultural harvesting head.

It is an object of this invention to provide such a system.

SUMMARY

In one arrangement, an agricultural harvester is provided comprising: aself-propelled vehicle; a feederhouse; a driveshaft having a proximalend and a distal end, wherein the driveshaft supported on thefeederhouse wherein the proximal end is configured to be driven inrotation to transmit power from the agricultural harvester to anagricultural harvesting head; and a first coupler fixed to the distalend of the driveshaft, the first coupler further comprising a couplerbody, a piston disposed inside the coupler body, and a first keymechanically coupled to the piston to be actuated by the piston, thefirst key being extendable from and retractable into the coupler bodywhen the piston is actuated.

The agricultural harvester may further comprise a second hydraulic fluidconnector supported on the driveshaft for rotation with respect to thedriveshaft.

The second hydraulic fluid connector may extend around and seals againstan outer surface of the driveshaft.

The second hydraulic fluid connector may enclose a hydraulic fluidpassageway in the driveshaft that communicates hydraulic fluid from asurface of the driveshaft to the piston.

The piston may be disposed in the coupler body to receive hydraulicfluid from the second hydraulic fluid connector and to be actuatedthereby.

The first coupler may further comprises a second key and a third keythat are configured to be simultaneously extendable from and retractableinto the coupler body when the piston is actuated.

The first key, the second key, and the third key may be equiangularlydisposed about a circumference of the coupler body.

The agricultural harvester may further comprise the agriculturalharvesting head, and the agricultural harvesting head may furthercomprise a frame; a reciprocating knife mounted on the frame; a seconddriveshaft having a first end drivingly coupled to the reciprocatingknife to drive the reciprocating knife and a second end; and a secondcoupler fixed to the second end of the second driveshaft, the secondcoupler having a cavity for receiving the first coupler.

An annular trough may be formed in a cylindrical side wall of thecavity.

The first key may extend into the annular trough when the piston isactuated.

A recess may be provided in the annular trough, and the first key may beconfigured to extend into the recess.

A side wall of the first key and a side wall of the recess may bedisposed to engage each other and to communicate torque from the firstcoupler to the second coupler sufficient to cause the first coupler torotate the second coupler about its longitudinal rotational axis.

The first coupler may further comprise a second key and a third key, andthe first key, the second key and the third key may be spacedequiangularly about the longitudinal rotational axis.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of an agricultural harvester and agriculturalharvesting head incorporating the present invention.

FIG. 2A is a cross-sectional view of an extendable driveshaft andcoupler that connect the agricultural harvester and agriculturalharvesting head of FIG. 1 taken at section line 2-2 in FIG. 1.

FIG. 2B is a detail cross-sectional view of the extendable driveshaftarrangement in the foregoing figures.

FIG. 3 is a cross-sectional view of the coupler of the foregoing figurestaken at section line 3-3 in FIG. 1.

FIGS. 4A-4F are cross-sectional views of the extendable driveshaft andcoupler of the foregoing figures at various stages of the engagement anddisengagement process.

FIG. 5 is a control system configured to operate the arrangement ofFIGS. 1-4F.

DETAILED DESCRIPTION

In the disclosure herein, the terms “front”, “forward”, “in front of”and the like refer to a forward direction of travel “V” indicated inFIG. 1. The forward direction of travel is a direction traveled by theagricultural harvester 100 when it is moving in a straight lineharvesting crops. The terms “rear”, “backward”, “behind”, “to the rearof”, and the like refer to the direction opposite to the forwarddirection of travel “V”. The term “lateral”, “width”, or “side-to-side”,refer to a direction perpendicular to the forward direction of travel“V”.

In FIG. 1, an agricultural harvester 100 comprises a self-propelledvehicle 102 from which a feederhouse 104 extends from the forward end ofthe self-propelled vehicle 102. The agricultural harvester 100 supportsan agricultural harvesting head 106, which is supported on the forwardfree end of feederhouse 104. An enclosed operator station 105 isdisposed on the self-propelled vehicle 102 above the feederhouse 104.The agricultural harvesting head 106 further comprises a frame 107 thatis elongate and extends substantially the entire width of theagricultural harvesting head 106.

In normal operation, the agricultural harvester 100 is driven throughthe field in a forward direction of travel “V”. As the agriculturalharvester 100 travels, it carries the agricultural harvesting head 106with it.

A reciprocating knife 108 disposed at the front of the agriculturalharvesting head 106 and is supported on the frame 107. The reciprocatingknife 108 extends substantially the entire lateral width of theagricultural harvesting head 106. The reciprocating knife 108 severscrop plants near their roots, and they fall upon the laterally extendingconveyors (not shown) of the agricultural harvesting head 106. They arethen conveyed toward the center of the agricultural harvesting head 106by conveyors, and are then sent rearward through a conveyor (not shown)that is disposed inside the feederhouse 104 and into the self-propelledvehicle 102 itself. Once in the self-propelled vehicle 102, the severedcrop plants are further processed by separating grain from materialother than grain (MOG) and saving the grain in a grain tank 110.Periodically, a vehicle travels alongside the self-propelled vehicle 102and receives grain from the grain tank 110 which is carried outward awayfrom the vehicle through a conveyor 112. In FIG. 1, the conveyor 112 isshown in its storage position. During unloading operations, however, theconveyor 112 is pivoted to extend laterally away from the side of theself-propelled vehicle 102.

The various moving devices in the agricultural harvesting head 106 aredriven by the engine in the self-propelled vehicle 102. The engine inthe self-propelled vehicle 102 transmits power to a driveshaft 114 thatis disposed at and supported on the front of the feederhouse 104,causing the driveshaft 114 rotate.

A first coupler 116 is fixed to one end of the driveshaft 114. The firstcoupler 116 is configured to mate with and drivingly engage a secondcoupler 118. The second coupler 118 is fixed to a second driveshaft 120.

When the first coupler 116 and the second coupler 118 are drivinglyengaged, the engine transmits power to the driveshaft 114, through thefirst coupler 116, into the second coupler 118, and then into the seconddriveshaft 120.

Second driveshaft 120 extends across the rear of the agriculturalharvesting head 106 to the left end of the agricultural harvesting head106 where it enters a first gearbox 122. A third driveshaft 124 iscoupled to the second driveshaft 120 and is driven thereby. Thirddriveshaft 124 extends forward adjacent to the left end of theagricultural harvesting head 106 and is coupled at its forward end to asecond gearbox 126. Second gearbox 126, in turn, is coupled to anddrives the reciprocating knife 108, the left side conveyor 128, theright side conveyor 130, the center conveyor 132, and other.

In FIG. 2, driveshaft 114, first coupler 116, and second coupler 118 areshown in the same spaced apart arrangement as they are shown in FIG. 1.Driveshaft 114 can be extended and retracted by the selective injectionand removal of hydraulic fluid from first hydraulic fluid connector 200.Driveshaft 114 has a first sliding shaft 202 and a second sliding shaft204 that are engaged each other to permit sliding relative movement ofthe first sliding shaft 202 with respect to the second sliding shaft204. The first sliding shaft 202 and the second sliding shaft 204 have amating surface features that permit them to slide with respect to eachother in a direction parallel to the longitudinal axes, yet permit themto communicate torque, and thus power one to the other. The matingsurface features include splines 206 on the outer surface of firstsliding shaft 202, and splines 208 disposed on an inner surface ofsecond sliding shaft 204. Splines 206 and splines 208 are the structuresthat mutually interengage with each other to permit first sliding shaft202 to slide with respect to second sliding shaft 204 whilesimultaneously permitting torque to be communicated from first slidingshaft 202 to second sliding shaft 204.

First sliding shaft 202 is disposed within second sliding shaft 204.First sliding shaft 202 has a hollow bore that receives a piston 210that is supported on a piston rod 212. Piston rod 212 is fixed to theouter end 214 of second sliding shaft 204.

The first hydraulic fluid connector 200 is supported for rotation on theouter surface of first sliding shaft 202. First hydraulic fluidconnector 200 comprises a connector body 216 that is generallycylindrical, a first hydraulic connector 218, a second hydraulicconnector 220, a first shaft seal 222, a second shaft seal 224, and athird shaft seal 226 that is disposed between the first hydraulicconnector 218 and the second hydraulic connector 220 in an axialdirection. The first shaft seal 222 and the second shaft seal 224 aredisposed at each end of the first hydraulic fluid connector 200 toprevent hydraulic fluid injected into the first hydraulic fluidconnector 200 from leaking out between the first hydraulic fluidconnector 200 and the outer surface of first sliding shaft 202. Thethird shaft seal 226 is disposed between the first hydraulic connector218 and the second hydraulic connector 220 to prevent hydraulic fluidfrom passing directly from the first hydraulic connector 218 to thesecond hydraulic connector 220 (and vice versa) without first passingthrough the longitudinal bore 228 of the first sliding shaft 202 andeffecting movement of the piston 210 and piston rod 212 disposed insidethe longitudinal bore 228.

In operation, the first hydraulic fluid connector 200 can turn freelyaround the outer surface of the first sliding shaft 202 upon the firstshaft seal 222, the second shaft seal 224, and the third hydraulic seal.The first sliding shaft 202 can rotate about its longitudinal axis, andcommunicate power from the driveshaft 114 to the second driveshaft 120and the first hydraulic fluid connector 200 can be held stationary.

This is particularly beneficial because it permits the first hydraulicfluid connector 200 to be connected to stationary hydraulic lines, andheld in place to extend and retract the driveshaft 114 as the driveshaft114 is rotating.

First hydraulic connector 218 and second hydraulic connector 220 areconnected to hydraulic lines to communicate hydraulic fluid to and fromthe first hydraulic fluid connector 200. The hydraulic lines, hydraulicvalves, electronic controls that are used to direct hydraulic fluid intoand out of the first hydraulic fluid connector 200 form no part of thisinvention. They are of conventional arrangement and are well known inthe art.

When hydraulic fluid is injected into the second hydraulic connector220, the hydraulic fluid passes into an annular gap 229 that is disposedbetween an inner surface of the connector body 216 and an outer surfaceof the first sliding shaft 202. The first hydraulic passageway 230 isdisposed to conduct hydraulic fluid from the annular gap 229, throughthe outer surface of the first sliding shaft 202 and thence to the rightside (in FIGS. 2A, 2B) of the piston 210. This hydraulic fluid causesthe piston 210 to move to the left (in FIGS. 2A, 2B) in the longitudinalbore 228. As the piston 210 moves to the left, hydraulic fluid in thelongitudinal bore 228 on the left side of the piston 210 is forced intoa second hydraulic passageway 232 in the piston rod 212. Hydraulic fluidentering the second hydraulic passageway 232 travels to the right end(in FIGS. 2A, 2B) of the piston rod 212 where it is released and returnsback to the first hydraulic fluid connector 200 traveling around theouter annular surface of the piston rod 212. Upon arriving back at thefirst hydraulic fluid connector 200, the hydraulic fluid meets a fourthshaft seal 234, which seals the outer surface of piston rod 212 againstthe inner surface of longitudinal bore 228. Fourth shaft seal 234prevents the returning hydraulic fluid from acting upon the right faceof the piston rod 212 and forces it to exit the first sliding shaft 202through third hydraulic passageway 236. Fluid exiting the first slidingshaft 202 enters an annular gap 237 that extends about the periphery ofthe first sliding shaft 202. Fluid entering the annular gap 237 entersthe first hydraulic connector 218 and is carried away from the firsthydraulic fluid connector 200. The annular gap 229 and the annular gap237 permit hydraulic fluid to be communicated to and from the firsthydraulic fluid connector 200 to the first sliding shaft 202 regardlessof the rotational position of the first hydraulic fluid connector 200with respect to the first sliding shaft 202.

Thus, hydraulic fluid injected into second hydraulic connector 220causes driveshaft 114 to extend. Similarly, injecting fluid into firsthydraulic connector 218 causes driveshaft 114 to retract.

Referring now to FIG. 4A, a second hydraulic fluid connector 400 isprovided on driveshaft 114 to communicate hydraulic fluid to and fromthe first coupler 116, causing the first coupler 116 to drivingly engagethe second coupler 118. The second hydraulic fluid connector 400comprises a second connector body 402 that is generally cylindrical, athird hydraulic connector 404, a fifth shaft seal 406, a sixth shaftseal 408 and a bearing 410.

The second hydraulic fluid connector 400 is supported on the bearing 410on second sliding shaft 204. This support permits it to rotate withrespect to the outer surface of the second sliding shaft 204. As withthe first hydraulic fluid connector 200, this permits the secondhydraulic fluid connector 400 to be held stationary as the driveshaft114 (and hence the second sliding shaft 204) rotate about itslongitudinal axis. As with the first hydraulic fluid connector 200, thispermits hydraulic lines to be connected to the third hydraulic connector404, and fluid to be introduced into or extracted from the thirdhydraulic connector 404 while the driveshaft 114 is rotating.

Fifth shaft seal 406 is located on the right side (in FIGS. 4A-4F) andextends between the inner surface of the second hydraulic fluidconnector 400 and the outer surface of second sliding shaft 204. Fifthshaft seal 406 prevents hydraulic fluid from leaking out of the secondhydraulic fluid connector 400 along the outer surface of second slidingshaft 204.

Sixth shaft seal 408 is located on the left side (in FIGS. 4A-4F) andextends between the inner surface of the second hydraulic fluidconnector 400 and the outer surface of the second sliding shaft 204.Sixth shaft seal 408 prevents hydraulic fluid from leaking out of thesecond hydraulic fluid connector 400 along the outer surface of secondsliding shaft 204.

Second sliding shaft 204 has a fourth hydraulic passageway 412 thatconducts hydraulic fluid from an outer surface of second sliding shaft204 to an inner chamber 414. Inner chamber 414 supports a piston 416 foraxial movement with respect to a longitudinal axis of driveshaft 114.Piston 416 seals against the inner surface of inner chamber 414, and isactuated by hydraulic fluid that is injected into or extracted fromthird hydraulic connector 404. Hydraulic fluid is conducted from thethird hydraulic connector 404 into an annular gap 417 extends about theouter surface of second sliding shaft 204. Hydraulic fluid in theannular gap 417 is conducted into the fourth hydraulic passageway 412,and thence into the inner chamber 414.

By providing the annular gap 417, hydraulic fluid may be conducted fromthe third hydraulic connector 404 to the piston 416 to actuate thepiston regardless of the rotational position of the second hydraulicfluid connector 400 with respect to the second sliding shaft 204.

In operation, hydraulic fluid from outside sources is injected into thethird hydraulic connector 404. This hydraulic fluid travels through thefourth hydraulic passageway 412 and into the inner chamber 414. Once inthe inner chamber 414, the hydraulic fluid acts against the face of thepiston 416. This causes the piston 416 to move axially with respect tothe driveshaft 114 (i.e. the second sliding shaft 204). I this movementof the piston 416 causes a coil spring 418 to push against the piston416 and be compressed.

When hydraulic fluid is released from the third hydraulic connector 404,the coil spring 418 releases its stored internal energy, and pushes thepiston 416 to the right (in FIGS. 4A-4F) with respect to the driveshaft114 (the second sliding shaft 204). This causes the hydraulic fluid inthe inner chamber 414 to be ejected from the third hydraulic connector404.

The piston 416 is a portion of the first coupler 116, which is fixed tothe outer end of the driveshaft 114 (the second sliding shaft 204).

The first coupler 116 comprises a coupler body 420 that is fixed to aflange 422 with threaded fasteners 424. Flange 422 extends outward fromthe leftmost end of the second sliding shaft 204 and provides a mountingpoint for the coupler body 420.

The coupler body 420 encloses the piston 416, as well as a conicalmember 426 that abuts the piston 416 and is actuated by the piston 416when the piston 416 moves axially.

Referring to FIG. 3, the coupler body 420 has three slots 300 that areequiangularly disposed with respect to each other in a planeperpendicular to the longitudinal axis of first coupler 116 and thelongitudinal axis of driveshaft 114. Each of the three circumferentialslots 300 receives and supports a corresponding one of keys 302. Each ofthe three circumferential slots 300 supports its corresponding key 302for radial movement toward and away from a longitudinal rotational axis434 of second coupler 118, which is coaxial with the driveshaft 114, thefirst sliding shaft 202, and the second sliding shaft 204.

Referring back to FIGS. 4A-4F, as hydraulic fluid from an outside sourceis injected into the third hydraulic connector 404, it causes the piston416 to translate to the left (in FIGS. 4A-4F). This movement causes theconical member 426 to also translate to the left with respect to thecoupler body 420. The conical member 426 has an outer conical surface428 that abuts an inner surface of each of the three keys 302. The threekeys 302 are constrained by the sidewalls of their respective threecircumferential slots 300 such that the movement of the conical member426 to the left causes the three keys 302 to move radially outward withrespect to the coupler body 420.

Thus, by introducing hydraulic fluid into the third hydraulic connector404, the three keys 302 of the first coupler 116 extend outward from thecoupler body 420. Similarly, by permitting hydraulic fluid to escapefrom the third hydraulic connector 404, the three keys 302 of the firstcoupler 116 retract inward into the coupler body 420.

The second coupler 118 has a coupler body 429 that is generallycylindrical and defines a cavity 430. The cavity 430 is generallycylindrical, and has a longitudinal axis that is parallel to thelongitudinal rotational axis 434. The opening of the cavity 430 isdefined by an opening in an end of the second coupler 118 that isopposite the second driveshaft 120. The opening of the cavity 430 facesthe first coupler 116.

The internal walls of the second coupler 118 that define the cavity 430are configured to receive and support the outer end of the first coupler116, which includes the three keys 302.

The internal walls of the second coupler 118 that define the cavity 430define a shoulder 432 in the form of an annulus that extends inwardlytoward the longitudinal rotational axis 434 of the second coupler 118.

The shoulder 432 extends around substantially the entire innercircumference of the cavity 430, such that it defines a trough 436 inthe form of an annulus. Trough 436 is disposed in the cylindrical sidewall of cavity 430. Trough 436 is coaxial with the longitudinalrotational axis 434 and coaxial with the second driveshaft 120.

Six recesses 438 are formed in the internal walls of the second coupler118 that define the cavity 430. The six recesses 438 are disposed at thebottom of the trough 436. The six recesses 438 have a longitudinalextent that is generally parallel to the longitudinal rotational axis434. The longitudinal extent of the recesses 438 is greater than thewidth of the recesses 438.

The recesses 438 are equiangularly spaced about the longitudinalrotational axis 434 as measured in a plane that is normal to thelongitudinal rotational axis 434. Each of the recesses 438 is disposedto engage an outer end portion 440 of a corresponding key 302.

Torque about the longitudinal rotational axis 434 is communicated fromthe first coupler 116 to the second coupler 118 through the keys 302that extend into the recesses 438.

FIG. 4A shows the two couplers in a starting position in which the firstcoupler 116 and the second coupler 118 are not engaged with the eachother. In a first step of a coupling process, hydraulic fluid isintroduced into the second hydraulic connector 220 of the firsthydraulic fluid connector 200 and is communicated into the longitudinalbore 228.

As hydraulic fluid fills the longitudinal bore 228, the hydraulic fluidpushes the piston 210 to the left (in FIG. 2A) causing driveshaft 114 toextend in length.

Eventually, each of the three keys 302 will contact an outer edge of theshoulder 432. This relationship is illustrated in FIG. 4 B. As hydraulicfluid continues to fill the longitudinal bore 228, and driveshaft 114continues to extend, the outer wall 442 of the trough 436 will pushagainst the three keys 302, causing them to slide inwardly in theirrespective circumferential slots 300, and translate radially inwardtoward the longitudinal rotational axis of the first coupler 116.

Continued filling of hydraulic fluid into the longitudinal bore 228 willeventually cause the three keys 302 to overtop the shoulder 432 andslide further into the second coupler 118 without further radialtranslation. This is shown in FIG. 4C.

Eventually, continued hydraulic fluid filling of the longitudinal bore228 will cause the three keys 302 to pass the shoulder 432 and bereceived into the trough 436.

An end surface 444 of the first coupler 116 will engage an inner surface446 of the cavity 430, preventing further movement of the first coupler116 into the second coupler 118.

The three keys 302 at this point are in the retracted positions andoriented radially inwardly of the trough 436.

Hydraulic fluid is then applied to the third hydraulic connector 404.Hydraulic fluid flowing into the first coupler 116 causes the three keys302 to extend outwardly and away from the rotational axis of the firstcoupler 116 until the three keys 302 abut the bottom of the trough. Thisposition is shown in FIG. 4D.

The three keys 302 extend further, however, when they are aligned withthree of the six recesses 438 that are formed in the bottom of thetrough 436. To be received into a corresponding three of the sixrecesses 438, the first coupler 116 must be rotationally aligned withrespect to the second coupler 118, such that the three keys 302 aredirectly above three corresponding recesses of the six recesses 438.

In order to do this, the operator engages the engine to driveshaft 114and begins to gently rotate driveshaft 114. The first coupler 116 isfixed to the end of driveshaft 114, and therefore rotates with thedriveshaft 114.

Eventually, the first coupler 116 rotates within the second coupler 118until the three keys 302 are aligned with three corresponding recessesof the six recesses 438. When this happens, the hydraulic pressureprovided by fluid introduced into the third hydraulic connector 404causes the outer end portions 440 of the three keys 302 to extendfurther from the rotational axis of the first coupler 116 and drop intothree corresponding recesses of the six recesses 438.

When the three keys 302 drop into three corresponding recesses of thesix recesses 438, the circumferentially facing sidewalls 448 of thethree corresponding recesses of the six recesses 438 abut thecircumferentially facing sidewalls 450 of the three keys 302. Theseabutting sidewalls communicate torque. From that moment, the firstcoupler 116 and the second coupler 118 are locked together as a singleunit.

As long as hydraulic fluid is not released from the third hydraulicconnector 404, the three keys 302 stay extended. The first coupler 116cannot be pulled out of the second coupler 118 because the surfaces ofthe three keys 302 will abut the shoulder 432. Similarly, any rotationof the first coupler 116 will be communicated to the second coupler 118because of the abutting relationship of the three keys 302 against theside walls of the three corresponding recesses of the six recesses 438.

In order to ensure that the first coupler 116 and the second coupler 118are properly oriented when this engagement process occurs, both thefirst coupler 116 and the second coupler 118 should be held in apredetermined alignment one with respect to the other when the operator,who is driving the self-propelled vehicle 102 from the operator station105, drives a self-propelled vehicle 102 forward and inserts thefeederhouse 104 into an aperture on the back of the agriculturalharvesting head 106, then raises the feederhouse 104 until agriculturalharvesting head 106 is raised and substantially or totally supported ona head support 452.

Head support 452 is typically in the form of one or more hooks thatextend forward and upward from the front of the feederhouse 104. Thesehooks are received in an aperture or apertures in the back of theagricultural harvesting head 106.

When the operator lifts the feederhouse 104 into the air usingfeederhouse lift cylinders (not shown) the agricultural harvesting head106 is supported in its proper position on the feederhouse 104. In thisposition, the first coupler 116 and the second coupler 118 aresubstantially coaxial, such that when the driveshaft 114 is extended,the first coupler 116 will be properly received into the second coupler118.

To ensure that the second coupler 118 is in the appropriate positionwhen the operator has raised the feederhouse 104 into the air and liftedthe agricultural harvesting head 106 into its proper orientation withrespect to the feederhouse 104, a coupler support 454 is provided thatextends from the agricultural harvesting head 106. The coupler support454 is positioned on the agricultural harvesting head 106 such that itsupports the second coupler 118 in its proper alignment with respect tothe first coupler 116.

The coupler support 454 can comprise brackets, straps, bolts, cradles,detents, or other devices having surfaces to hold the second coupler 118in proper alignment. In one arrangement, the coupler support 454includes several spring-loaded ball detents that engage correspondingrecesses in the second coupler 118. In another arrangement, the couplersupport 454 is a cradle extending underneath the second coupler 118 tohold it in proper alignment.

The first coupler 116 and the second coupler 118 may be provided with arange of movement to accommodate pivoting in flexing of the agriculturalharvesting head 106 on the feederhouse 104. In one common arrangement,an agricultural harvesting head 106 can be tilted side to side withrespect to the feederhouse 104 and the self-propelled vehicle 102 inorder to better follow ground terrain and harvest crops.

This arrangement, however, means that the driveshaft 114 and the seconddriveshaft 120 must be free to move up and down with respect to theagricultural harvesting head 106 as the agricultural harvester 100travels through the field harvesting crop.

To provide this freedom of movement during normal operation, theoperator performs an additional step as part of the coupler engagementprocess described above. Once the operator has engaged the two couplerstogether to communicate torque and prevent them from being pulled apart,he couples a source of hydraulic fluid under pressure to the firsthydraulic connector 218. As described above, this causes the driveshaft114 to retract and its overall length to be reduced. As the length ofthe driveshaft 114 is reduced, the driveshaft 114 pulls the firstcoupler 116 and the second coupler 118 (which are bound together at thispoint) to the right (in FIG. 2A), and pulls the second coupler 118 outof its coupler support 454. The coupler support 454 will be movedrelatively with respect to the second coupler 118 to the position shownin dashed lines in FIG. 2A the second coupler 118 is no longercontacting the coupler support 454, and a clearance “C” (in FIG. 2A) isgenerated between the bottom of second driveshaft 120 and the couplersupport 454.

The second coupler 118 can translate without being disengaged from thesecond driveshaft 120 because the second driveshaft 120 has a splinedsection 456 defined by an inner tube 458 and an outer that is receivedinside an outer tube 460. The splined section 456 is dimensioned suchthat when the second coupler 118 is withdrawn from the coupler support454 and clearance “C” is provided, there is still sufficient engagementbetween the inner tube 458 and the outer tube 460 of the seconddriveshaft 120 that power can be communicated from the driveshaft 114 tothe first gearbox 122, and thence to the reciprocating knife 108 and theother driven elements on the agricultural harvesting head 106.

A flexible joint 462 is provided along the length of the seconddriveshaft 120. This flexible joint 462 permits the agriculturalharvesting head 106 to pivot with respect to the feederhouse 104. Theflexible joint 462 comprises, for example, a universal joint or constantvelocity joint.

Referring to FIG. 5, a control system 500 for controlling thearrangement of FIGS. 1-4F is illustrated. Control system 500 comprisesan operator input device 502, an electronic control unit (ECU) 504, afirst valve 506, a hydraulic fluid source 508, a hydraulic fluidreservoir 510, and a second valve 512.

The operator input device 502 may be a stick, lever, button, dial, knob,shaft encoder, keyboard, touch screen, voice-recognition system, orother electronic operator input device capable of indicating to ECU 504that the operator desires an engagement or disengagement of driveshaft114 to second driveshaft 120. In one arrangement, the operator inputdevice 502 is located in the cab of the agricultural harvester 100 (seeFIG. 1). In an alternative arrangement, the operator input device 502 islocated on or adjacent to the feederhouse 104 where the operator canengage and disengage the driveshaft 114 to the second driveshaft 120while observing the engagement process and the disengagement process.

The ECU 504 is connected to the operator input device 502 to receive asignal indicating the operator's desire to engage or disengagedriveshaft 114 to second driveshaft 120.

The first valve 506 is coupled to the hydraulic fluid source 508 toreceive fluid therefrom, and to control the flow of hydraulic fluid toand from the second hydraulic fluid connector 400. The first valve 506is coupled to the hydraulic fluid reservoir 510 to return hydraulicfluid from the second hydraulic fluid connector 400 to the hydraulicfluid reservoir 510. The ECU 504 is coupled to the first valve 506 toactuate the first valve 506. The first valve 506 is connected to thethird hydraulic connector 404.

The second valve 512 is coupled to the hydraulic fluid source 508 toreceive fluid therefrom, and to control the flow of hydraulic fluid toand from the first hydraulic fluid connector 200. The second valve 512is coupled to the hydraulic fluid reservoir 510 to return hydraulicfluid from the first hydraulic fluid connector 200 to the hydraulicfluid reservoir 510. The ECU 504 is coupled to the second valve 512 toactuate the second valve 512. The two hydraulic fluid conduits extendingfrom the second valve 512 are connected to the first hydraulic connector218 and the second hydraulic connector 220.

In a first mode of operation, when the driveshaft 114 and the seconddriveshaft 120 are disengaged, the ECU 504 is programmed to monitor thestate of the operator input device 502, and when the operator inputdevice 502 is actuated, to actuate the second valve 512 to extend thedriveshaft 114 so that the first coupler 116 engages the second coupler118.

The ECU 504 is programmed to then actuate the first valve 506 to extendthe keys 302 until they engage the second coupler 118.

The ECU 504 is programmed to then rotate the driveshaft 114 for aportion of a turn until the keys 302 until the three keys 302 arealigned with three corresponding recesses 438 of the six recesses 438.The hydraulic pressure acting against the piston 416 (the hydraulicpressure being provided by first valve 506) will cause the keys 302 toextend into the three corresponding recesses 438.

The ECU is programmed to then actuate the second valve 512 and retractthe driveshaft 114. This causes the first coupler 116 and thenow-engaged second coupler 118 to move rightward (in FIGS. 4A-4F andFIG. 5) until the second coupler is pulled away from coupler support454. At this point, the driveshaft 114 and the second driveshaft 120 arecoupled together and the operator can use his operational controls (notshown) in the traditional manner to drive the agricultural harvestinghead 106 and harvest the field.

In a second mode of operation, when the driveshaft 114 and the seconddriveshaft 120 are engaged, the ECU 504 is programmed to monitor thestate of the operator input device 502, and when the operator inputdevice 502 is actuated, to actuate the second valve 512 to extend thedriveshaft 114 until the second coupler 118 is again supported by thecoupler support 454.

The ECU 504 is then programmed to actuate the first valve 506 to permithydraulic fluid to flow from the second hydraulic fluid connector 400 tothe hydraulic fluid reservoir 510 and the keys 302 to be responsivelyretracted into the coupler body 429.

The ECU 504 is then programmed to actuate the second valve 512 toretract the driveshaft 114, thereby separating the first coupler 116from the second coupler 118 and leaving the second coupler 118 supportedby the coupler support 454.

In the arrangement described above, the ECU 504 performs thesesuccessive drive shaft engagement steps automatically. Alternatively,the ECU 504 can be programmed to respond to the operator input device502 to perform each of the above steps sequentially as each step issequentially commanded by the operator. Alternatively, the ECU canautomatically perform two or more of the sequential steps above insequence and wait for the operator to command the next sequential stepusing the operator input device 502.

The description above and the figures herein are not intended toillustrate every possible way of constructing a device in accordancewith the invention. The description and the figures merely illustratethe principles behind the invention and at least one way of constructingat least one device in accordance with the invention. The invention isdefined by the claims below.

I claim:
 1. An agricultural harvester (100) comprising: a self-propelledvehicle (102); a feederhouse (104); a driveshaft (114) having a proximalend and a distal end, wherein the driveshaft (114) supported on thefeederhouse (104) wherein the proximal end is configured to be driven inrotation to transmit power from the agricultural harvester (100) to anagricultural harvesting head (106); and a first coupler (116) fixed tothe distal end of the driveshaft (114), the first coupler (116) furthercomprising a coupler body (420), a piston (416) disposed inside thecoupler body (420), and a first key (302) mechanically coupled to thepiston (416) to be actuated by the piston (416), the first key (302)being extendable from and retractable into the coupler body (420) whenthe piston (416) is actuated.
 2. The agricultural harvester (100) ofclaim 1, further comprising a second hydraulic fluid connector (400)supported on the driveshaft (114) for rotation with respect to thedriveshaft (114).
 3. The agricultural harvester (100) of claim 2,wherein the second hydraulic fluid connector (400) extends around andseals against an outer surface of the driveshaft (114).
 4. Theagricultural harvester (100) of claim 3, wherein the second hydraulicfluid connector (400) encloses a hydraulic fluid passageway in thedriveshaft (114) that communicates hydraulic fluid from a surface of thedriveshaft (114) to the piston (416).
 5. The agricultural harvester(100) of claim 2, wherein the piston (416) is disposed in the couplerbody (420) to receive hydraulic fluid from the second hydraulic fluidconnector (400) and to be actuated thereby.
 6. The agriculturalharvester (100) of claim 2, wherein the first coupler (116) furthercomprises a second key (302) and a third key (302) that are configuredto be simultaneously extendable from and retractable into the couplerbody (420) when the piston (416) is actuated.
 7. The agriculturalharvester (100) of claim 6, wherein the first key (302), the second key(302), and the third key (302) are equiangularly disposed about acircumference of the coupler body (420).
 8. The agricultural harvester(100) of claim 1, further comprising the agricultural harvesting head(106), the agricultural harvesting head further comprising a frame(107); a reciprocating knife (108) mounted on the frame (107); a seconddriveshaft (120) having a first end drivingly coupled to thereciprocating knife (108) to drive the reciprocating knife (108) and asecond end; and a second coupler (118) fixed to the second end of thesecond driveshaft (120), the second coupler having a cavity (430) forreceiving the first coupler (116).
 9. The agricultural harvester (100)of claim 8, wherein an annular trough (436) is formed in a cylindricalside wall of the cavity (430).
 10. The agricultural harvester (100) ofclaim 9, wherein the first key (302) extends into the annular trough(436) when the piston (416) is actuated.
 11. The agricultural harvester(100) of claim 10, wherein a recess (438) is provided in the annulartrough (436), and further wherein the first key (302) is configured toextend into the recess (438).
 12. The agricultural harvester (100) ofclaim 11, wherein a side wall of the first key (302) and a side wall ofthe recess (438) are disposed to engage each other and communicatetorque from the first coupler (116) to the second coupler (118)sufficient to cause the first coupler (116) to rotate the second coupler(118) about its longitudinal rotational axis (434).
 13. The agriculturalharvester (100) of claim 12, wherein the first coupler (116) furthercomprises a second key (302) and a third key (302), and further whereinthe first key (302), the second key (302) and the third key (302) arespaced equiangularly about the longitudinal rotational axis (434).